Today, art historians have noted the distinctive calligraphic style of the faked Harunobu signature, the use of Western-style perspective, and the somewhat less delicate figures in works by "Harunobe" (Kōkan).

Kōkan lived in Edo, was a student of rangaku (Dutch studies) in addition to his pursuits as an artist, and interested in astronomy in particular.

Australia is present with an approximation of shape quite unknown to Nagakubo Sekisui [ja]; Brazil again stretches eastward in deformity; Japan is at the far east of a sheet, but this is a modern map.

The ever-original Shiba Kokan describes himself in the colophon as introducing copper engraving technologies to Japan.

Later impressions added considerably to the surrounding decorations, with small scenes of whaling, of hills and harbours and plant dissection; they are also more fully colored, in homage to Willem Blaeu or popular taste.